Acceleration responsive microswitch



July 28, 1959 P. R. WEAVER 2,897,306

ACCELERATION RESPONSIVE MICROSWITCH Original Filed June 29. 1954 u I 2 2 34 i: 4 4 4 H- 1 1 1 FIG.

INVENTOR PRESTO/V R. WEAVER ATTORNEY United States Patent ACCELERATION RESPONSIVE MICROSWITCH Preston R. Weaver, Nyack, N.Y., assignor to the United States of America as represented by the Secretary of the Navy application June 29, 1954, Serial No. 440,299, now Patent No. 2,867,382, dated January 6, 1959. Dizidgeg and this application October 11, 1957, Serial No.

9 Claims. (Cl. 200-61.45)

(Granted under Title 35, US. Code (1952), sec. 266) The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

The present invention relates to a microswitch and more particularly to a microswitch that is responsive to acceleration.

The microswitch of the present invention is usable in various apparatus, and particularly as a sensing element in a maneuvering loads accelerometer. The microswitch when used as a sensing element registers the actual number of times the accelerometer has been subjected to predetermined accelerations.

This application is a division of application Serial No. 440,299, filed June 29, 1954, for Maneuvering Loads Accelerometer, now Patent No. 2,867,382.

An object of the present invention is the provision of a microswitch that is responsive to acceleration.

Other objects and many of the attendant advantages of this invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein:

Fig. 1 is a plan view of the microswitch of the present invention;

Fig. 2 is a view in section taken along line 2-2 of Fig. 1 showing the microswitch in its normal open position; and

Fig. 3 is a view in section taken along line 3-3 of Fig. 1 showing the microswitch in its closed position.

The microswitch of Fig. 1 consists of a body 25 formed of Bakelite, plastic or similar non-conducting material. A raised portion 26 is formed at one end of the body upon which a snap-action type switch leaf 27 is mounted by means of screw 28 and retaining washer 29 to form a terminal. The interior portion of switch leaf 27 is cut out to define oppositely extending tongue 31 and short projection 32, the adjacent ends of which are joined by compression spring 33. The tongue 31 is longitudinally slotted as at 34 to receive a bolt 35 which secures the two halves of a mass 36 to the tongue, the slot permitting the mass to be selectively positioned on the tongue. A central opening 37 is provided in the body 25 to permit vertical movement of the mass 36. A pair of damping plates 38 and 39 are secured to opposite sides of the opening 37 by means of bolts and nuts 40. The free end of switch leaf 27 is provided with a contact 41 near its extremity which lies between the spaced contacts 42 and 43. The lower contact 42 is secured to the body 25 by a terminal forming screw 44 and extends beneath the contact 41. The upper contact 43 overlies the contact 41 and is spaced above the body 25 by means of a terminal forming screw 45 and spacer 46.

In operation it will be seen that as mass 36 is moved from the position of Fig. 2 by an acceleration force of proper intensity, the tongue 31 is flexed against the force of spring 33 and the spring is compressed. As mass 36 moves toward the position of Fig. 3, spring 33 flexes switch leaf 27 upwardly, thus causing contact 41 to disengage contact 42' and to engage. contact 43 to close the counter circuit. When the acceleration force has receded to 25% below the actuating value, the tongue 31 forces. mass 36 back to the position of Fig. 2 and spring 33. flexes switch leaf 27 downwardly, which moves contact 41 away from contact 43 and into engagement with contact 42.

Obviously many modifications and variations of the present invention are possible in the light of the above teachings. It is therefore to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described.

What is claimed is:

1. In a maneuvering loads accelerometer of the character described, an acceleration-responsive microswitch comprising a terminal; a pair of vertically spaced contacts; a snap-action switch leaf having one end fixed to the terminal and the other end free to move between said pair of contacts, the interior of said leaf being cut away to form a tongue and an oppositely extending projection the adjacent ends of which are joined by a compression spring, and a mass adjustably mounted on said tongue; whereby the free end of the leaf will be shifted from the lower contact of said pair to the upper contact of said pair in response to an acceleration.

2. An acceleration responsive microswitch comprising a body having an opening therethrough, a terminal fixed to said body on one side of said opening, a first contact fixed to said body on the other side of said opening, a flexible leaf fixed at one end thereof to said terminal and extending over said opening and having its other end operatively positioned to engage said first contact, a second contact on said other end of said leaf, and means attached to said leaf to move in said opening in response to acceleration for moving said second contact on said leaf into and out of engagement with said first contact.

3. The combination set forth in claim 2 and means adjustably mounting said acceleration responsive means on said leaf in a direction away or towards said terminal.

4. The combination set forth in claim 2 wherein the interior of said flexible leaf is cut away to form a tongue and an oppositely extending projection the adjacent ends of which are joined by a compression spring.

5. An acceleration responsive microswitch comprising a body having an opening therethrough, a terminal fixed to said body on one side of said opening, a pair of vertically spaced contacts fixed to said body on the other side of said opening, a flexible leaf fixed at one end thereof to said terminal and extending over said opening and having its other end positioned between said pair of vertically spaced contacts, a contact on said other end of said flexible leaf, and means attached to said leaf to move in said opening in response to changes of acceleration for moving said contact on said leaf into and out of engagement with said pair of contacts.

6. The combination set forth in claim 5 and means adjustably mounting said acceleration responsive means on said leaf in a direction away or towards said terminal.

7. The combination set forth in claim 5 wherein the interior of said flexible leaf is cut away to form a tongue and an oppositely extending projection the adjacent ends of which are joined by a compression spring.

8. In a maneuvering loads accelerometer including a source of current and a plurality of registering units connected in parallel therewith, an acceleration-responsive microswitch connected in series with said source ahead of said units, said switch having a snap-action leaf with one end afiixed to a terminal and the other end free to move between a pair of contacts, and a mass mounted on said leaf for moving the free end of the leaf from one of said pair of contacts to the other of said pair of contacts in response to an acceleration of a certain magnitude.

9. In a maneuvering loads accelerometer including a source of current and a plurality of registering units connected in parallel with said source, an acceleration-responsive microswitch connected in series with said source ahead of said units, said switch having a snap-action leaf fixed at one end to a terminal and the other end free to move between a pair of vertically spaced contacts, and means on said leaf for movin the free end from the lower of said pair of contacts to the upper of said pair of contacts in response to an acceleration, said means being adjustable to vary the acceleration level to which the switch will respond.

References Cited in the file of this patent UNITED STATES PATENTS 2,521,015 McLaren et al. Sept. 5, 1950 2,800,546 Reitler July 23, 1957 2,807,690 Schwaneke Sept. 24, 1957 2,812,398 Mickman Nov. 5, 1957 2,821,588 Fisher Jan. 28, 1958 

